The ledge is not very visible from Buffalo Road when there are leaves on the trees. You can park nearby at the Precision Lumber parking lot or along the road just before that lot. Logging trucks use the road so consider getting well off the side. There is a bit of poison ivy along the road but not up at the ledge. You can usually find a spot to avoid it.
The three giant potholes at Plummer's Ledge are quite large and deep and were cut straight down into a ledge on its 45-degree side slope. The potholes were thought to be formed by the plunging of melt water through vertical cracks or crevasses in the glacial ice. The water carrying boulders, cobbles, and gravel churned with intense cutting power, drilling into the slope of the granite ledge. Several of the early visitors have only seen the small potholes on top of the ledge. You should explore from below/in front of the ledge to see the really big ones. Those are actually not marked in the map above.
To log this Earthcache send me the answers to these questions: 1. How wide and deep (from the top of the lip on the ledge) is the largest pothole with water in it (approximately)? 2. What is a moulin? 3. What direction does the ledge face?